regular expressions

[pixelwraith]

i am making calculations and want to check that the user has entered only digits and not just a leading zero or only a zero
this is what i have used
if ($answers[2] =~/\D/)
{
exit;
}
to check that only digits have been used but cant figure out how to incorporate leading zeros or only a zero
i tried
if ($answers[2] =~/\D^0/)
{
exit;
}
and a few other versions

can someone help out with the correct syntax? :)

[dswimboy]

$answers[2] =~ /^0/; // will match a leading zero
if ($answers[2] == 0) // will be true if all zeroes

[pixelwraith]

thanks!
heres another
if ($answers[2] =~ /^(0)|(\D)/)

[dswimboy]

that would return true for leading zero numbers...at least i think it should. the caret symbol matches the beginning of a line, unless in brackets (or probably anywhere other than the beginning of a string).

[pixelwraith]

if it checks only for leading zeros its the same as checking for 0, 00, 000 etc :)